Published online May 15, 2020. doi: 10.5495/wjcid.v10.i1.1
Peer-review started: March 17, 2020
First decision: April 3, 2020
Revised: April 15, 2020
Accepted: April 24, 2020
Article in press: April 24, 2020
Published online: May 15, 2020
Processing time: 56 Days and 2.9 Hours
Coronaviruses are among the largest group of known positive - sense RNA viruses with a wide range of animal hosts as reservoir. In the last two decades, newly evolved coronaviruses such as the severe acute respiratory syndrome coronavirus (SARS-CoV) which caused the infamous 2002 outbreak, the Middle East respiratory syndrome coronavirus (MERS-CoV) which caused an outbreak in 2012, and now the SARS-CoV-2 [responsible for the current coronavirus disease 2019 (COVID-19)] have all posed notable threats to global public health. But, how does the current COVID-19 outbreak compare with previous coronaviruses diseases? In this review, we look at the key differences between SARS-CoV, MERS-CoV, and SARS-CoV-2, and examine challenges in determining accurate estimates of the severity of COVID-19. We discuss coronavirus outbreaks in light of key outbreak severity indicators including, disease fatality, pathogen novelty, ease of transmission, geographical range, and outbreak preparedness. Finally, we review clinical trials of emerging treatment modalities and provide recommendations on the control of COVID-19 based on the mode of transmission of the coronaviruses. We also recommend the development and use of a standardized predictive epidemic severity models to inform future epidemic response.
Core tip: In this review, we look at differences and similarities between severe acute respiratory syndrome coronavirus, Middle East respiratory syndrome coronavirus, and severe acute respiratory syndrome coronavirus 2 and we discuss the challenges in the determination of case fatality rates in pandemics like the current and propose the need for standardization of predictive epidemic severity models that considers critical factors that can influence the severity of outbreaks.